Power feed apparatus



April 11, 1961 Filed Aug. 21, 1957 C. F. CURRAN, JR., ET AL POWER FEED APPARATUS 5 Sheets-Sheet 1 440 INVENTORS CHARLES E CURRAN,JR. 3 HAROLD KAZARIAN EWILLIAM TINGLE JMXM j me) ATTORNEY Aprll 11, 1961 c, F, cu R JR" ETAL 2,978,872

POWER FEED APPARATUS Filed Aug. 21. 1957 5 Sheets-Sheet 3 MW NW Q Q we M23 QQ mm a mi z Wk NW Q Q m 0 Twm R ER QR Kw sh 93w E msv \W INVENTORS. CHARLES E CURRAN.JR. HAROLD KAZARIAN & WILLIAM TINGLE fihZd/a $5M JIM ATTORNEY April 1961 c. F. CURRAN, JR., EI'AL 2,978,872

POWER FEED APPARATUS 5 Sheets-Sheet 4 Filed Aug. 21, 1957 INVENTORS. CHARLES E CURRAN, JR. HAROLD KAZARIAN :fiWILLlAM TINGLE ATTORNEY April 11, 1961 c QURRAN, JR" ETAL 2,978,872

POWER FEED APPARATUS Filed Aug. 21, 1957 5 Sheets-Sheet 5 73 AIR AIR //42 9a 9 ll4| 94 we 27 HOV MAIN SWITCH LIGHT SAFETY L 6 {\8O iLxfiiL R 40 TIZQCONTROL SWITCH I un 5mg cm ggvrm V 8 9 045N010 SWITCH SVVYTZH 4 a1 8;

70 LIMIT SWITCH wwvA/vc/AIG ELECTRIC m TIMER SWITCH 5285 CONTACT RELAY INVENTORS CHARLES F CURRAN JR RETRACT TMEA? 86 m HARQLD KAZARIAN W|LL|AM TINGLE BY m a I00 SOLENOID coll. JM

ATTORNEY POWER FEED APPARATUS Charles F. Curran, Jr., and Harold Kazarian, Providence, and William Tingle, Pawtucket, R.I., assignors to The Holdsworth Manufacturing Co. Inc., Pawtucket, R.I., acorporation of Rhode Island Filed Aug. 21, 1957, Ser. No. 679,499

8 Claims. (Cl. 60-97) This invention relates to hydro-electric actuated me chanical apparatus for producing relative advance and withdrawal between a tool and work material with advance feeding of the work material in timed relation to the advance and withdrawal of the tool and means for returning the feed to an initial starting position. More particularly, this invention relates to mechanical apparatus under control of electrical timing means employing fluid actuated driving means.

One of the objects of the present invention is to provide a mechanical apparatus with fluid actuated driving means under control of an electrical timing device.

Another object of the present invention is to provide a work carriage with mechanical indexing means, actuated by an air cylinder under control-of an electrical timing unit.

And still another object of the present invention is to provide a spindle which is rotated by an electric motor and advanced by a hydraulic system and returned rapidly by a pressure air system with means to reciprocate the spindle back and forth for chip clearance as it moves forward.

And still another object of the present invention is to provide a spindle which is rotated by an electric motor and fed and retracted by a pressure air system with electrical timing apparatus influencing the feed to reciprocate the spindle in the feed movement for chip clearance.

Other objects of the present invention will become apparent in part and be pointed out in part in the following specification and claims.

Referring to the drawings in which similar characters of reference indicate corresponding parts in all the figures:

Figure 1 is a side elevational view of the new and improved power feed apparatus.

Figure 2 is a plan view of Figure 1.

Figure 3 is a transverse cross-sectional view taken along line 33 of Figure 2 looking in the direction of the arrows.

Figure 4 is a transverse cross-sectional view similar to Figure 3, taken along line 4-4 of Figure 2 looking in the direction of the arrows.

Figure 5 is a schematic diagrammatic view of the hydraulic control mechanism.

- Figure 6 is a circuit diagram of the electrical system.

Figure 7 is a perspective view of the mechanical parts constituting the new and improved power feed apparatus.

Figure 8 is a schematic cross-sectional view showing the air piston connected to the ratchet lever.

Figure 9 is a fragmentary cross-sectional view taken along line 5 9 of Figure 2.

Figure 10 is a perspective view of a work piece operated upon by the present invention.

Figure 11 is a schematic diagrammatic view of a pressure air system for actuating the various pistons and is a modified form of mechanism shown in Figure 5.

Referring to the drawings,- the new and improved power feed apparatus consists-of a bed or platform 11 secured to a stand 12 provided with legs 13 and 14.

An electrically rotated, air reciprocated, hydraulically controlled spindle head or tool carriage is generally indicated at 15 and comprises an electric motor 16, a housing 17, a spindle 18, a chuck 19 mounted on spindle 18 and a drill 20 held in chuck 19. Housing 17 is secured for lateral adjustment to bed 11.

Across head generally indicated at 21 comprises a reversed Z shaped housing-22 (see Figures 1, 2, 3, 7 and 9) adjustably mounted to bed 111. Housing 22 is pro vided with a rectangular recess 23 which serves the function of a track. Squareplates 24 and 25 block rectangular recess 23 on opposite ends. A square threaded shaft26 is rotatively mounted in square plates 24 and 25.

A work carriage generally indicated by reference numeral 27, having the appearance of a C clamp comprises a body 28 having an upper arm 29 and a lower arm 30. Body 28 is provided with a square thread which is adapted to cooperate with square threaded shaft 26. Body 28 is also adapted to be slidably mounted in rectangular recess 23 so that rotation of square threaded shaft 26 causes body 28 to slide in rectangular recess 23 which serves the function of a track for work carriage 27.

A plurality of thumb screws 31 are located in upper arm 29. A work piece 32 may be placed on lower arm 39. A filler piece 33 may be interposed between work piece 32 and body 28.. Thumb screws 31 will hold work piece 32 against lower arm 30.

A drill guide 34 (Figures 1, 2, 3 and 7) secured to bed 11 by means of nut 35 guides drill 20 through bushing 34A (Figures 3 and 7) as it moves toward and away from work piece 32.

A ratchet wheel 36 is fixed to the end of square threaded shaft 26. A ratchet lever 37, provided with a pawl 38 pivotally mounted at 40, is pivotally mounted to square threaded shaft 26 with pawl 38 engaging the teeth of ratchet wheel 36.

A handle 39 is removably secured to the end of square threaded shaft 26 to manually turn shaft 26 for purposes of adjustment, setting and return of Work carriage 27 to starting position after it has been advanced in the opposite direction by mechanism presently to be described.

Referring to Figure 5 there is shown in diagrammatic representation the air operated hydraulic system, comprising the rapid control approach cylinder 40B, the feed control cylinder 41, spindle 18, pressure advance cylinder 42, hydro-electric control switch 43, solenoid actuated four Way valve 44, directional control check valves 45, 46, 47, three way solenoid actuated valve 91 and air operated cylinder 101.

Three way solenoid actuated valve, generally indicated at 91 (see Figures 5, 7, 8 and 11), consists of a housing 92, a piston 93 provided with two piston heads 94, 95 dividing the valve into chambers 96, 97 having ports 98, 99, respectively, and a solenoid 100 operatively connected to piston 93. Chamber 96 is provided with an exhaust port 96A. Chamber 97 is provided with an exhaust port 97A.

The air operated cylinder, generally indicated at 101 (see Figures 1, 2, 5, 7, 8 and 11), consists of a housing 102, a piston rod 103,21 piston head 104, two ports 105, 106 and chambers 107, 108. A conduit 110 connects ports 98 and 105. A conduit 111 connects ports 99 and 106. Ratchet lever 37 is pivotally connected at 112 to piston rod 103.

Solenoid actuated four way valve, generally indicated at 44 (see Figures 5 and 11), consists of a housing 44A, a piston rod 71 provided with two piston heads 72, 76 dividing the valve into chambers 74, 77 and 77A. Chamber 74 is provided with a port 75. Ghamber 77A is provided with a port 63. Piston'rod 71. is provided with a solenoid coil 71A on one and and a coil spring 713 on the other end.

Rapid control approach cylinder, generally indicated at 40B (see Figures 1 2,4, and 7), is providednwith an air chamber 79 and, an oil chamber 57A separated by a sliding ram 57.; A ram stop 58 is provided in. air chamber 79. V C

Feed control cylinder, generally indicated at 41 (see Figures 1, 5 and 7) is provided with an air chamber 78 and an oil chamber 64 separated by a sliding plug 61.

Pressure advance cylinder, generally indicated at 42 (see Figures 1, 2, 4, 5, 7 and 11) is provided with a housing 42A having an air chamber 54A and an oil chamber 90 separated by a piston 54 operatively connected to spindle 18. Piston 54 is integrally connected toa piston rod 126. I

Hydro-electric control switch, generally indicated at 43 (see Figures 1, 2, 5 and 7) consists of a housing 433 divided into three chambers 1, 2 and 3. A plunger 68 is slidably mounted'in chamber 1 with the end of plunger 68 projecting into chamber 2. A spring 114 yieldingly urges plunger 68 into a preselected position within chamber 1. 'Two electrical contacts 141, 142 are located in chamber 2. A pivotally mounted contact arm 140, yieldingly held in a pre-selected position by spring 140A, engages either electrical contact 141 or 142 as determined by the actuation of plunger 68 which engages one end of contact arm 140, thus forming an electric switch, generally indicated at 70. Two electrical contacts 131A and 132A are located in chamber 3. A pivotally mounted contact arm 130A located in chamber 3 is yieldingly held in pre-selected position by spring 128A, thus forming a limit switch, generally indicated at 81. A lever 127A slidingly mounted in housings 42A and 433 provides an operating connection between piston rod 126 and con tact arm 130A. t

A series of conduits provide, an air or oil circuit between the various mechanisms forming the air operated hydraulic system.

The air system comprises a conduit 50 provided with an air filter 51, a pressure regulator 52 and an air oiler 53. Thereafter, conduit 50 divides into two branch conduits 50A and 50B. Conduit 50A provides air to chamber 97. Conduit 50B provides air tochamber 77. Conduit 73 provided with a flow control valve 143 conducts air from chamber 77 to air chamber 54A. A conduit 62 provided with a flow control valve 144 has a branch conduit 59.

Conduit 62 provides an air connection from chamber 77A to air chambers 78 and 79. r

A closed oil circuit is provided consisting of a conduit 55 connected to oil chamber 90 on one end, and which divides into two branches on the other end. One branch connects to a directional control check valve 47. The other branch connects to a directional control check valve 46. A conduit 55A connects directional control check valve 47 with diretional control check valve 46 and thereafter divides into two branches forming conduits 56 and 60. Conduit 60 connects conduit 55A through directional control check valves 46,, 47 with .oil chamber 64. Conduit 56 connects conduit 55A through directional control check valves 46, 47 with oil chamber 57A. A third directional control check valve 45 is connected on one side to conduit 56 and on the other side to conduit 87 which in turn is connected to oil chamber 64. A conduit 67 connects oil chamber 90 with chamber 1.

In operation, air under pressure from a source of air supply (not shown) enters conduit 50 and passes through air filter 51, pressure regulator 52 and air oiler- 53.,

1 act to move piston. head 104 to the left as viewed ,in

camera r. W

. 4 Figure 5. Chamber 107 exhausts to the atmosphere through conduit 110, chamber 96 and exhaust port 96A. Movement of piston head 104 to the left will cause ratchet lever 37, through piston rod 103, to swing upon shaft 26 and thereby rotate ratchet wheel 36 the distance of one tooth through the engagement of pawl 38.

In timed sequence, as will presently appear, solenoidcoil 100 will be energized to overcome the tension of spring 116 and thereby actuate piston 93 causing piston heads 94, '95 to slide to the left as viewed in Figure 5. Piston head 94 will slide sufficiently to allow air from conduit 50A, passing into chamber 97, to pass into conduit and through flow control valve 1141, into chamber 107 wherethe air will act on the other side of piston head 104, thereby moving piston head 104 to the right as viewed in Figure 5. Chamber 108 exhausts to the atmosphere through conduit 111 and exhaust port 97A. This movement of piston head 104 reverses the direction of movement of ratchet lever 37 and thereby carries pawl 38 into position to engage the next tooth on ratchet wheel 36, whereby shaft 26 is poised for the next indexing increment.

Simultaneously with the sliding of piston head 94, to the left, piston head 95 moves to the left so that chamber 97 is blocked from contact with conduit 111. v

The air passing through conduit 50B will enter chamber 77. With piston heads 72, 76 in the position shown in Figure 5, air will pass from chamber 77 into conduit 73, through flow control valve 143 and into air chamber 54A, thereby to move piston 54 and spindle 18 to the right as viewed in Figure 5. This is the 'start of the forward motion of spindle 18.

The movement of piston 54 to the right forces oil from oil chamber 90 into conduit 55 into directional control check valves 47, 46. As illustrated in Figure 5, directional control check valve 47 will block the flow of oil to conduit 55A. However, directional control check valve 46 will permit oil to flow into conduits 55, 60, simultaneously.

The oil flowing through conduit 56 will enter oil chamber 57A and thereby move ram 57 to the right, as viewed in Figure 5, forcing air out of air chamber 79, through conduit 59, through flow control valve 144 and conduit 62, into chamber 77A, to be exhausted to the atmosphere through port 63. 7

The oil flowing through conduit 60 will enter oil chamber 64 and thereby move slidingplug 61 to the left as viewed in Figure 5, to exhaust the air in air chamber 78 through conduit 62, flow control valve 144, chamber 77A to the atmosphere through port 63.

An electric circuit controls the cycle of operation of the machine. A component part, electric switch 70 controls solenoid coil 71A of solenoid actuated four way valve 44. Valve 44 controls the forward and reverse movement of piston 54 and spindle 18. Limit switch 81 controls a chip clearance action as will presently appear.

The movement of piston 54 to the right as viewed in Figure 5, under the influence of the air in air chamber 54A, simultaneously with the forcing of oil into conduit 55, forces oil into conduit 67 and chamber 1. The oil thereby forces plunger 68 to the right, as viewed in Figure 5, against the tension of spring 114, pivoting contact arm from the positionshown in Figure 5 where contact arm engages contact 141 to a position where con- ,tact arm 140 engages contact 142. ,Thereby de-energizing solenoid coil 71A and releasing piston rod 71 to the action ofspring 71B whereby piston heads 72, 76 are slid to the right, as viewed in Figure 5. The return cycle of spindle 18'is thus initiated. Piston head 72 moves to the opposite side of conduit 73. Thereby connecting conduit 73 with chamber 74 and port 75. Piston head 76 moves .to the opposite-side of conduit 62. Thereby, blocking port 63 and connecting conduit 62 with chamber 77 and -the source of air supply frorn conduits'50, 50B. flow ing through conduit 62 and flow control valve 144 will enter air chamber 78 and through conduit 59, enter air chamber 79. The air in air chamber 79 will act on ram 57 to slide ram 57 to the left, as viewed in Figure 5. Thereby forcing oil out of oil chamber 57A into conduit 56.- Air entering air chamber 78 will act on sliding plug 61 to move sliding plug 61 to the right, as viewed in Figure 5. Thereby, forcing oil out of oil chamber 64 into conduits 60, 87, simultaneously. The oil in conduit 87 will pass through directional controlcheck valve 45 into conduit 56 to join the oil flowing out of oil chamber 57A. The oil in conduit 61) will also flow into conduit 56, simultaneously with the oil from conduit 87. Directional control checkvalve 46 will block the flow of oil at that joint from entering conduit 55. However, directional control check valve 47 will permit oil in conduits 56 andSSA to flow into conduit 55 and oil chamber 90. Thereby, toslide piston 54, to the left as viewed in Figure 5. Air is thereby forced out of air chamber 54A into conduit 73, flow control valve 143, chamber 77 and exhausted to the atmosphere through port 75. With the movement of piston 54- to the left, as viewed in Figure 5, oil in chamber 1 is permitted to flow through conduit 67 to oil chamber 90, thereby, releasing plunger 68 to the action of spring114 and the shifting of contact arm 140 from engagement. with contact 142 to engagement with contact 141 through spring 140A. Solenoid 71A is thereby again energized to slide piston rod 71 to the left, as viewed in FigureS, against the tension of spring 71B. Thus piston heads 72, 76 will slide into the position shown in Figure 5 for the start of another drilling cycle as previously described.

A feature of the present invention is a chip clearance action imparted to spindle 18 through a limit switch'81. Limit switch 81 is a'component part 6f the electric circuit.

The movement of piston 54 to the right, as viewed in Figure 5, at the start of the forward motion of spindle 18, slid piston rod 126 out of engagement with lever 127A to thereby release contact arm 130A to the action of spring 128A to shift contact arm 130A from engagement with contact 131A to engagement withcontact 132A. Contacts 131A and 132A are electrically connected to a timing device, generally indicated by reference numeral 225 Figure 1.

An electric timer, generally indicated at 225 (Figure 1) is provided in the electric circuit. Timer 225 may be of any commercial design but as illustrated is a Model LET-l4-A-2 manufactured by the Lumenite Electric Company of 407 South Dearborn Street, Chicago, Illinois. A selector switch 80 forms an inherent part of timer 225.

In Figure 6 there is shown a diagram of the electric circuit. Selector switch 80 (see Figures 1, 2, 4 and 6) is manually set to automatic operative position to start the flow of electric current from a source of supply (not shown) 'to' a cycle start switch 89. The current will close cycle start switch 89 and pass to limit switch 81.

.Lirnit switch 81 is normally open. Limit switch 81 when energized allows current to flow to cycle control relay 82 to close relay 82.

An advancing timer 83 is provided to control the period of time spindle 18 is in forward movement. Cycle control relay 82 starts or activates advancing timer 83. Advancing timer 83 is in series with electrical contacts 141, 142 of electric switch 70. Advancing timer83 makes and breaks contact to control the current to solenoid 71A, thereby controlling the movement of piston rod 71 and piston heads 72, 76 admitting air from chamber 77 toconduits 73, 62 and causing piston 54 to slide back and forth as previously described. Advancing timer 83 advances piston 54 a predetermined distance based on a time interval and retracts piston 54 a lesser distance based upon a shorter time interval. In this manner piston 54 andspindle 18 are moved progressively forward with a short stroke recipro'catingmovement.

Upon completing its cycle, advancing timer 83 opens limit switch 81 to stop the flow of currentto cycle control relay 82 and thereby place cycle control relay 82 in open condition. The completion of the cycle of advancing timer 83 also causes timer 83 to energize and thereby close a limit switch 84. The closing of limit switch 84 energizes and thereby closes a control or contact relay 85. Control relay 85 energizes retract timer 86 whereby solenoid coil 71A is de-energized, thereby releasing piston rod 71 to the action of spring 713 for the purpose of shifting piston 54 to the left as viewed in Figure 5. Thus, the energizing and de-energizing of solenoid coil 71A causes piston 54 to reciprocate back and forth or to the left and to the right as viewed in Figure 5.

As piston 54 reciprocates in chip clearance action it progressively moves forward. This forward movement forces hydraulic fluid in oil chamber 90 to pass through conduit 67 and into chamber 1 to act on plunger 68 to shift contact arm 140 as previously described.

Referring to Figure 11 wherein is shown a modified form of pressure air system to advanceand retract spindle 18, it will be noted that the closed hydraulic fluid circuit shown in Figure 5 is eliminated, thus eliminating rapid control approach cylinder 48B, feed control cylinder 41 and directional control check valves 45, 46, 47. Conduit 62 in Figure 5 identified as 62A in Figure 11 connects chamber 77A with chamber 90, thus converting chamber 90 to a pressure air chamber in place of a hydraulic fluid chamber. Piston 54 is thus operated by alternate application of pressure air to a selected one of its sides instead of application of pressure air on one side or pressure fluid on the opposite side.

As piston 54 moves forward, to the right in Figure 11. piston rod 126 in contact with lever 127 moves forward until piston rod 126 is beyond lever 127 so that lever 127 under the influence of spring 128 causes contact arm 13%? to shift from contact 131 to contact 132. Movement of contact arm 130 of limit switch 81A opens the electric circuit between cycle start switch 89 and control relay 82 and closes limit switch 84 to energize control relay 85 to start retract timer 86.

'Retract timer 86 as previously described will cause piston 54 to move in the direction of arrow 113, thereby causing piston rod 126 to engage, override and depress lever 127 to shift contact arm 130 from contact 132 to contact 131 causing the current to flow from cycle start switch 89 to control relay 82 to repeat the cycle. This cycle repeats itself until a counter 123 breaks the circuit to stop the machine.

A counter 123 (see Figures 2 and 3) is fixed to housing 22. A projection 124 on piston 103 engages an arm 125 on counter 123, so that as piston 103 is reciprocated it actuates arm 125 to indicate the number of reciprocations of piston 103.

Counter 123 is provided with an electric switch 126 connected to the electric circuit, so that after a predetermined number of revolutions of the counter, switch 126 is actuated by the counter to open or break the electrical circuit to stop the machine. Switch 126 is manually set through knob 127.

When selector switch 80 is manually set, electric motor 16 is energized to rotate spindle 18.

The manual operation of selector switch 80 and the manual operation of cycle start switch button 89 opens the circuit to safety switch to de-energize (or stop thefiow of current to) light 121 (the light goes out) to infogm the operator that the electrical circuit is energrze A safety mechanism in the form of a solenoid valve 440, Figure 6, which is normally closed and located in conduit 50 and connected to the electric circuit (see Figures 1, 2 and 6) serves the function of a safety device. When there is a power failure from the source of electrical power supply the valve will remain closed blocking out the source of air supply from conduit 50,, thus preventing the entire mechanism from starting, i.e. air cannot advance piston 54 and spindle 18. This prevents the machine from starting with a drill in work engagement, a condition which normally would break a drill when the spindle started to rotate.

When the main switch 441 (Figure 6) is placed in the on position, electric current first energizes solenoid valve 440 to open it and allow pressure air from conduit 50 to reach four way solenoid actuatedvalve 44 and three way solenoid actuated valve 91 through conduit 50A.

Flow control valves 1141, 1142, 143 and 144 regulate the flow of air to pistons 104, 54, sliding plug 61 and ram 57 respectively to controlthe speed of pistons 104, 54, sli ding plug 61 and ram 57.

Figure 10 depictsa work piece 32 having a plurality of small diameter holes 5 provided by the previously described mechanism.

Having shown and described preferred embodiments of the present invention, by way of example, but realizing that structural changes could be made and other examples given without departing from either the spirit or scope of this invention.

What we claim is: p

1. A machine comprising a horizontally moving work carriage and a horizontally reciprocating tool carriage positioned at right angles to said work carriage, each "carriage movable relatively to the other in a horizontal plane, an air operated cylinder provided with a piston head, mechanical indexing means connecting said piston head to said work carriage to index said work carriage horizontally through the movement of said piston head, a source of fluidpressure for said piston head, a solenoid actuated valve having a plunger interposed between said source of fluid pressure and said piston head, an electrical timing mechanism controlling said plunger to operate said plunger'in opposite directions alternately to control the fluid pressure to said piston head to operate said piston head in opposite directions alternately and thereby impart horizontal indexing movement to said work carriage through said mechanical means.

2. A machine comprising a work carriage and a tool carriage each movable relatively to the other, an air operated cylinder provided with a piston head and attached rod, mechanical means connecting said piston head and attached rod to said work carriage, a source of air pressure for said piston head, a solenoid actuated valve having a plunger interposed between said source of air pressure and said piston head, an electrical timing mechanism controlling said plunger to operate said plunger in opposite directions alternately to control the air pressure to said pistonhead to operate said piston head in opposite directions alternatelyand thereby impart movement to said work carriage through said mechanical means, an air system consisting ofa four way solenoid actuated valve having a second plunger, and a pressure advance cylinder having a piston, a limit switch connected to said electrical timing mechanism and actuated and controlled by said piston, air from said source of air pressure passing to said four way solenoid actuated valve, said electrical timing mechanism controlling the passage of air through said four way solenoid actuated valve to V operate said piston in opposite directions alternately in time relation to the alternate movement of said piston head. i V

, 3. A machine comprising a work carriage and a tool carriage each movable relatively to the other, an air operated cylinder provided with a piston head and attached rod, mechanical means connecting said piston head and attached rod'to said work carriage, 'a source of air pressure for said piston head, a solenoid actuated valve having a plunger'interposed between said source of air pressure and said piston head, an electrical timing mechanism controlling said plunger to operate said plunger in opposite directions alternately to control the airpressure to said piston head to operate said piston head and attachedrod in opposite directions alternately and'thereby impart movement to said work carriage through said mechanical means, an air system consisting .of a four way solenoid actuated valve having a second plunger, and a pressure advance cylinder having a piston, an electrical circuit comprisingsaid electrical timingmechanism provided with an advance timer, a retracting timer, and cooperating with actuating means for said four way solenoid actuated valve and said solenoid actuated valve, air from said source of, air pressure passing to said four way solenoid actuated valve, said electrical timing mechanism under control of said advance timer and 'said retracting timer controlling the passage of air through said four way solenoid actuated valve to reciprocate saidpiston in short strokes in the,forward direction of movement, and to operate said piston in forward and backward movement alternately in timed relation to the alternate movement of said piston head.

4. A tool carriage comprising an electrical circuit and a hydraulic system consisting of a four way solenoid actuated valve having a plunger, and a pressure advance cylinder having a piston, an electric motor, a spindle rotatively connected to said electric motor, said piston operatively connected to said spindle, said electricaljcircuit comprising said electric motor, a limit switch, an electrical timing mechanism provided with an advance timer, a retracting timer, and actuating means for said four way solenoid actuated valve, 'said limit switch actuated by said piston, a source of air pressure passing to said four way solenoid actuated valve, said electrical timing mechanism under controlof said advance timer and said retracting timer controlling .the passage of air :through said four way solenoid actuated valve to reciprocate said piston and spindle in short strokes in the forwarddirection of movement, and to operate said piston in a backward movement, said limit switch When actuated by said piston, breaking said electrical circuit to the actuating means for said four way solenoid actuated valve to de-energize said four way solenoid actuated valve whereby said second plunger is shifted to cause backward movement of said piston.

5. A machine comprising a work carriage having a cross head provided with a track, a body member slidably mounted in said track, a threaded shaft operatively connected to said body member and rotatively mounted in said cross head, a tool carriage connected to be moved back and forth horizontally toward and away from said work carriage, the body member moving back and'forth transversely to the movement of the tool carriage, an air operated cylinder provided with a piston head having a piston rod located on said cross head, a ratchet mechanism consisting of a toothed wheel secured to said threaded shaft and a lever pivotally connected on one end to said piston rod and rotatively mounted to said threaded shaft, a pawl pivotally mounted to said lever and engageable and disengageable with said toothed Wheel, a counter provided with an arm located on said cross arm, said piston rod engaging said arm to advance said counter with the movement of said piston head, an electric circuit, a switch in said circuit operatively con nected to said counter, a timing mechanism in said electric circuit, a source of air supply, a three way solenoid actuated valve interposed between said source of .air supply and said air operated cylinder, said timing mechanism controlling'actuation of said three 'way'solenoid actuated valve to allow said air supply to operate said carriage and ahorizontally reciprocating tool carriage positioned at right angles to said work carriage, each carriage movable relatively to the other in a horizontal plane, an air operated cylinder provided with a piston head, a rod attached to said piston head, a shaft rotatably mounted in said work carriage, a Wheel provided with ratchet teeth, fixed to said shaft, a lever pivotally mounted to said shaft, a pawl pivotally mounted on said lever and engageable and disengageable with said ratchet teeth, said lever pivotally connected to said rod, a source of air supply, a three way solenoid actuated valve interposed between said source of air supply and said air operated cylinder, an electrical timing mechanism controlling the actuation of said three way solenoid actuated valve to allow said air supply to operate said piston head in opposite directions alternately and thereby pivot said lever on said shaft through said rod to intermittently rotate said shaft through the engagement of said pawl with said ratchet teeth to move said work carriage in one horizontal direction.

7. A machine comprising a horizontal moving work carriage and a horizontal reciprocating tool carriage, each carriage movable relative to the other in a horizontal plane, said tool carriage having a spindle and a piston connected to said spindle, hydraulic fluid engaging one side of said piston, a source of air supply, a four way solenoid actuated valve connected to said source of air supply, said air supply passing through said four way actuated valve to engage the other side of said piston, an electrical timing mechanism, a three way solenoid actuated valve, said electrical timing mechanism controlling the actuation of said four way solenoid actuated valve in timed relation with the actuation of said three way solenoid actuated valve, a hydroelectric switch operatively connected to said electrical timing mechanism, and to said hydraulic fluid on one side of said piston, mechanical means connecting said piston and hydroelectric switch, whereby said air supply moves said piston and said spindle in one direction, said hydraulic fluid moves said piston and said spindle in the opposite direction,- the movement of said spindle being toward and away from said work carriage in timed relation to the movement of said work carriage, and said hydro-electric switch through the movement of said piston actuating said mechanical means, actuates said electrical timing mechanism to control both said three way and said four way solenoid actuated valves.

8. A machine comprising a work carriage and a tool carriage each movable relatively to the other, an air operated cylinder provided with a piston head and attached rod, mechanical means connecting said piston head and rod to said Work carriage to move said carriage through the movement of said piston head and rod, a source of air pressure for said piston head, a solenoid actuated valve having a plunger interposed between said source of air pressure and said piston head, an electrical timing mechanism controlling said plunger to operate said plunger in opposite directions alternately to control the air pressure to said piston head to operate said piston head and rod in opposite directions alternately and thereby impart movement to said work carriage through said mechanical means, an air system and a closed oil system, said air system consisting of a four way solenoid actuated valve having a second plunger, a rapid control approach cylinder having a ram connected on one side to said air system and on the opposite side to said closed oil system, a feed control cylinder having a sliding plug connected on one side to said air system and on the opposite side to said closed oil system, a pressure advance cylinder having a piston connected on one side to said air system and on the opposite side to said closed oil. system, electrical switch means operatively connected to said piston and forming part of said electrical timing mechanism, air from said source of air pressure passing to said four way solenoid actuated valve, said electrical timing mechanism controlling the passage of air through said four way solenoid actuated valve to said piston to move said piston toward the work, the oil on the opposite side of said piston actuating said rapid control approach cylinder and said feed control cylinder and thereby controlling the movement of said piston toward the work, the movement of said piston toward the work actuating said electrical switch means and in sequence with said electrical timing mechanism interrupting the electrical circuit to de-energize said four way solenoid actuated valve and thereby shift said second plunger to pass air through said four way solenoid actuated valve to said ram and to said sliding plug whereby movement of said ram and sliding plug under the influence of said air, causes oil in said closed oil circuit to move said piston away from said work.

References Cited in the file of this patent UNITED STATES PATENTS 1,817,552 Galloway Aug. 4, 1931 1,911,138 Clute et a1. May 23, 1933 2,020,868 Barnes et al Nov. 12, 1935 2,324,727 Shartle July 20, 1943 2,675,657 Taggart et al. Apr. 20, 1954 2,802,452 Hogeman Aug. 13, 1957 2,830,475 Jones Apr. 15, 1958 

